The dose-limiting toxicity and feasibility of administering escalating doses of DCPSA-RNA will be defined. As a secondary endpoint, the ability of DCPSA-RNA to induce proxtate specific antigen (PSA)-specific immune responses will be evaluated. Finally, the anti-tumor effect based on PSA (biochemical) response criteria will be defined. Prostate cancer is the most commonly diagnosed cancer in men and is the second major cause of cancer deaths in the Western civilization. Although metastatic prostate cancer responds initially to androgen ablative therapy, hormonal therapies have not produced a major improvement in overall survival despite several decades of laboratory and clinical investigation. Growing evidence suggests that active immunotherapy, particularoy dendritic cells (DC) based vaccines, may prove to be a viable and clinically effective therapeutic option for patients with advanced or metastatic prostate cancer. Peripheral blood mononuclear cells collected through peripheral blood leukapheresis are processed for DC generation immediately. Mononuclear cells are separated, resuspended, and cultured for 7 days in GM-CSF and IL-4. Harvested dendritic cells will be pulsed in PSA-RNA solution and subsequently cryopreserved. An aliquot from the lot of the PSA-RNA pulsed and cryopreserved DC supernatants will be tested for sterility prior to administration.